Investigations

• Urinalysis and urgent microscopy  
  • Look for, or request examination for
    • dysmorphic red blood cells  ^b  
    • pigmented granular casts   ^b  

     

• blood count (including MCV and blood smear) ^d
• Urea, electrolytes and glucose ^{b c}
• ECG ^c  
• Chest X-ray ^d
• Doppler ultrasound to assess kidney size, symmetry, echogenicity, and presence of renal artery stenosis ^b

• if cerebral infarction or subarachnoid haemorrhage suspected ^d
  • CT head
  • Lumbar puncture

   

• if primary hyperaldosteronism suspected
  • renin and aldosterone levels ^c  

   

• if a phaeochromocytoma is suspected ^c  
  • plasma catecholamines
  • 24h urine for catecholamine breakdown products

   

• if renal artery stenosis suspected:  
  • gadolinium-enhanced MR angiography ^b
  • CT angiography ^b
  • interarterial angiography ^a

    Less helpful tests include

    • captopril scintigraphy  ^b 
    • captopril test. ^b 

   

• if other renal disease suspected: 
  • serological work-up and/or renal biopsy as judged appropriate by a renal specialist ^d

Note